Initial Commit

database/perl/lib/Net/FTP/dataconn.pm

@@ -0,0 +1,237 @@
+##
+## Generic data connection package
+##
+
+package Net::FTP::dataconn;
+
+use 5.008001;
+
+use strict;
+use warnings;
+
+use Carp;
+use Errno;
+use Net::Cmd;
+
+our $VERSION = '3.13';
+
+$Net::FTP::IOCLASS or die "please load Net::FTP before Net::FTP::dataconn";
+our @ISA = $Net::FTP::IOCLASS;
+
+sub reading {
+  my $data = shift;
+  ${*$data}{'net_ftp_bytesread'} = 0;
+}
+
+
+sub abort {
+  my $data = shift;
+  my $ftp  = ${*$data}{'net_ftp_cmd'};
+
+  # no need to abort if we have finished the xfer
+  return $data->close
+    if ${*$data}{'net_ftp_eof'};
+
+  # for some reason if we continuously open RETR connections and not
+  # read a single byte, then abort them after a while the server will
+  # close our connection, this prevents the unexpected EOF on the
+  # command channel -- GMB
+  if (exists ${*$data}{'net_ftp_bytesread'}
+    && (${*$data}{'net_ftp_bytesread'} == 0))
+  {
+    my $buf     = "";
+    my $timeout = $data->timeout;
+    $data->can_read($timeout) && sysread($data, $buf, 1);
+  }
+
+  ${*$data}{'net_ftp_eof'} = 1;    # fake
+
+  $ftp->abort;                     # this will close me
+}
+
+
+sub _close {
+  my $data = shift;
+  my $ftp  = ${*$data}{'net_ftp_cmd'};
+
+  $data->SUPER::close();
+
+  delete ${*$ftp}{'net_ftp_dataconn'}
+    if defined $ftp
+    && exists ${*$ftp}{'net_ftp_dataconn'}
+    && $data == ${*$ftp}{'net_ftp_dataconn'};
+}
+
+
+sub close {
+  my $data = shift;
+  my $ftp  = ${*$data}{'net_ftp_cmd'};
+
+  if (exists ${*$data}{'net_ftp_bytesread'} && !${*$data}{'net_ftp_eof'}) {
+    my $junk;
+    eval { local($SIG{__DIE__}); $data->read($junk, 1, 0) };
+    return $data->abort unless ${*$data}{'net_ftp_eof'};
+  }
+
+  $data->_close;
+
+  return unless defined $ftp;
+
+  $ftp->response() == CMD_OK
+    && $ftp->message =~ /unique file name:\s*(\S*)\s*\)/
+    && (${*$ftp}{'net_ftp_unique'} = $1);
+
+  $ftp->status == CMD_OK;
+}
+
+
+sub _select {
+  my ($data, $timeout, $do_read) = @_;
+  my ($rin, $rout, $win, $wout, $tout, $nfound);
+
+  vec($rin = '', fileno($data), 1) = 1;
+
+  ($win, $rin) = ($rin, $win) unless $do_read;
+
+  while (1) {
+    $nfound = select($rout = $rin, $wout = $win, undef, $tout = $timeout);
+
+    last if $nfound >= 0;
+
+    croak "select: $!"
+      unless $!{EINTR};
+  }
+
+  $nfound;
+}
+
+
+sub can_read {
+  _select(@_[0, 1], 1);
+}
+
+
+sub can_write {
+  _select(@_[0, 1], 0);
+}
+
+
+sub cmd {
+  my $ftp = shift;
+
+  ${*$ftp}{'net_ftp_cmd'};
+}
+
+
+sub bytes_read {
+  my $ftp = shift;
+
+  ${*$ftp}{'net_ftp_bytesread'} || 0;
+}
+
+1;
+
+__END__
+
+=head1 NAME
+
+Net::FTP::dataconn - FTP Client data connection class
+
+=head1 SYNOPSIS
+
+    # Perform IO operations on an FTP client data connection object:
+
+    $num_bytes_read = $obj->read($buffer, $size);
+    $num_bytes_read = $obj->read($buffer, $size, $timeout);
+
+    $num_bytes_written = $obj->write($buffer, $size);
+    $num_bytes_written = $obj->write($buffer, $size, $timeout);
+
+    $num_bytes_read_so_far = $obj->bytes_read();
+
+    $obj->abort();
+
+    $closed_successfully = $obj->close();
+
+=head1 DESCRIPTION
+
+Some of the methods defined in C<Net::FTP> return an object which will
+be derived from this class. The dataconn class itself is derived from
+the C<IO::Socket::INET> class, so any normal IO operations can be performed.
+However the following methods are defined in the dataconn class and IO should
+be performed using these.
+
+=over 4
+
+=item C<read($buffer, $size[, $timeout])>
+
+Read C<$size> bytes of data from the server and place it into C<$buffer>, also
+performing any <CRLF> translation necessary. C<$timeout> is optional, if not
+given, the timeout value from the command connection will be used.
+
+Returns the number of bytes read before any <CRLF> translation.
+
+=item C<write($buffer, $size[, $timeout])>
+
+Write C<$size> bytes of data from C<$buffer> to the server, also
+performing any <CRLF> translation necessary. C<$timeout> is optional, if not
+given, the timeout value from the command connection will be used.
+
+Returns the number of bytes written before any <CRLF> translation.
+
+=item C<bytes_read()>
+
+Returns the number of bytes read so far.
+
+=item C<abort()>
+
+Abort the current data transfer.
+
+=item C<close()>
+
+Close the data connection and get a response from the FTP server. Returns
+I<true> if the connection was closed successfully and the first digit of
+the response from the server was a '2'.
+
+=back
+
+=head1 EXPORTS
+
+I<None>.
+
+=head1 KNOWN BUGS
+
+I<None>.
+
+=head1 AUTHOR
+
+Graham Barr E<lt>L<gbarr@pobox.com|mailto:gbarr@pobox.com>E<gt>.
+
+Steve Hay E<lt>L<shay@cpan.org|mailto:shay@cpan.org>E<gt> is now maintaining
+libnet as of version 1.22_02.
+
+=head1 COPYRIGHT
+
+Copyright (C) 1997-2010 Graham Barr.  All rights reserved.
+
+Copyright (C) 2013-2014, 2020 Steve Hay.  All rights reserved.
+
+=head1 LICENCE
+
+This module is free software; you can redistribute it and/or modify it under the
+same terms as Perl itself, i.e. under the terms of either the GNU General Public
+License or the Artistic License, as specified in the F<LICENCE> file.
+
+=head1 VERSION
+
+Version 3.13
+
+=head1 DATE
+
+23 Dec 2020
+
+=head1 HISTORY
+
+See the F<Changes> file.
+
+=cut